Flow control valve

ABSTRACT

Flow control valves may be positioned downstream of water meters to increase pressure and compress entrained water vapour passing through the meters. However, turbulence within such valves can cause the valve&#39;s head to move radially, bending a shaft within the valve which may break. Accordingly, there is provided a flow control valve comprising: a housing having a flow passage; a valve seat defined within the flow passage; a valve head moveable to a closed position to engage the valve seat and seal the flow passage; a shaft secured to the valve head; a support slidingly mounting the shaft within the housing; a spring biasing the valve head to the closed position and configured to maintain the valve head in the closed position until a predetermined pressure is applied; and a guide assembly extending along at least a portion of the flow passage to constrain radial movement of the valve head.

CROSS REFERENCE TO RELATED APPLICATIONS

This application in a continuation of U.S. patent application Ser. No.17/582,107, filed Jan. 24, 2022, entitled “Flow Control Valve” which isa continuation of U.S. patent application Ser. No. 16/433,176, now U.S.Pat. No. 11,255,443, filed Jun. 6, 2019, entitled “Flow Control Valve”,which claims priority to U.S. Provisional Patent Application No.62/681,834,filed Jun. 7, 2018, entitled “Flow Control Valve” and U.S.Provisional Patent Application No.62/746,910, filed Oct. 17, 2018, alsoentitled “Flow Control Valve,” wherein each of the foregoing isincorporated by reference in its entirety herein.

FIELD

The present disclosure generally relates to valves and more particularlyto flow control valves.

BACKGROUND

Flow control valves are used to control the flow of fluids, such aswater. U.S. Patent Application Publication No. 2009/0289207 to Barredaet al. discloses a valve assembly that is adapted to be disposed withina water supply line. The valve assembly is structured to reduce orsignificantly eliminate the passage of air and water vapour through awater meter measuring the water supply line. The valve body includes asealing structure which is biased under a predetermined force intosealing relation with an inlet of valve assembly. The predeterminedforce is sufficient to prevent displacement of the sealing structure outof the sealing relation with the inlet until the force from a desiredwater pressure is exerted thereon. As a result, any air or water vapourwithin the water supply line will be compressed to reduce the flowmeasured through the water meter, thereby preventing unnecessary chargesbeing made to a metered facility.

U.S. Patent Application Publication No. 2014/0182717 to Edgeworthdiscloses a system and an associated valve assembly that are adapted toincrease the efficiency of an upstream water meter. By way of the valveassembly, entrained gas bubbles can be removed from a water supply.This, in turn, increases the density of the water running through thewater meter. This ensures that the water meter is not inaccuratelyincluding entrained air or water vapour as metered water. The result ismore accurate water readings and reduced utility bills.

While the contributions of existing flow control valves are laudable,improvements are generally desired. It is therefore an object of thepresent disclosure to provide a new and useful flow control valve thatcan be used in a water supply line.

SUMMARY

It should be appreciated that this Summary is provided to introduce aselection of concepts in a simplified form that are further describedbelow in the Detailed Description of Embodiments. This Summary is notintended to be used to limit the scope of the claimed subject matter.

According to an aspect, there is provided a flow control valvecomprising: a housing having an inlet, an outlet and a flow passageextending therebetween; a valve seat defined within the flow passage; avalve head positioned in the flow passage and movable between a closedposition and an open position, wherein the valve head engages the valveseat in the closed position to seal the flow passage; a spring retainedwithin the housing, the spring biasing the valve head to the closedposition and configured to maintain the valve head in the closedposition until a predetermined pressure is applied to the valve headfrom fluid at the inlet; and a guide assembly extending along at least asection of the flow passage, the guide assembly configured to engage thevalve head to constrain radial movement of the valve head.

In some embodiments of the flow control valve, one or more of thefollowing may be provided: the guide assembly is configured to constrainradial movement of the valve head when moving between the closedposition and the open position; the guide assembly extends along theentire section of the flow passage; the guide assembly comprises atleast one guide rail secured within the housing and positioned to engagethe valve head; at least one void is formed in the valve head, the atleast one void shaped to slidingly receive the at least one guide rail;and the at least one guide rail comprises a plurality of guide railsthat are circumferentially positioned around the valve head.

In some embodiments of the flow control valve, one or more of thefollowing may be provided: the flow control valve further comprises ashaft secured to the valve head and a support slidingly mounting theshaft within the housing; the support abuts an end of the spring toretain the spring within the housing; the support comprises a reversiblebar secured to the housing and having a first face that is shaped topre-compress the spring by a first amount and a second face that isshaped to pre-compress the spring by a second amount, the second amountbeing greater than the first amount; the predetermined pressure isapproximately 45 psi when the spring is pre-compressed by the firstamount and wherein the predetermined pressure is approximately 60 psiwhen the spring is pre-compressed by the second amount; the valve headcomprises a removable wear cap that engages the valve seat when thevalve head is in the closed position; the removable wear cap is formedof Teflon™; the valve seat is defined by a narrowed portion of thehousing and the valve head is completely withdrawn from the narrowedportion when the valve head is in the open position; and the valve seatand the valve head define a seal plane and wherein the valve headcomprises a flat face that does not extend upstream of the seal planewhen in the closed positon and that is positioned downstream of the sealplane when in the open position.

According to another aspect, there is provided a flow control valvecomprising: a housing having an inlet, an outlet and a flow passageextending therebetween, the housing defining a valve seat within theflow passage; a valve plug retained within the housing and movablebetween a closed position and an open position, the valve plug having avalve head for sealingly engaging the valve seat when the valve plug isin the closed position, to substantially prevent fluid flow through theflow passage, and further having a valve body extending downstream fromthe valve head and configured to slidingly engage an inner surface ofthe housing as the valve plug moves between the closed position and theopen position, to constrain radial movement of the valve plug; and aspring retained within the housing, the spring biasing the valve plugtowards the closed position and configured to maintain the valve plug inthe closed position until a predetermined pressure is applied to thevalve head from fluid at the inlet.

In some embodiments of the flow control valve, one or more of thefollowing may be provided: the valve body comprises a plurality of finsthat extend radially outward beyond an outer diameter of the valve headand are configured to slidingly engage the inner surface of the housingas the valve plug moves between the closed position and the openposition, to constrain radial movement of the valve plug; the fins arearranged to constrain radial movement in a plurality of radialdirections; the plural of radial directions includes a horizontal radialdirection and a vertical radial direction; and the fins are arranged inone of a cross-shape and a Y-shape.

In some embodiments of the flow control valve, one or more of thefollowing may be provided: the valve head has a flat upstream face thatis configured to be completely retraced from the valve seat; the housingcomprises a sleeve and an insert secured to the sleeve, and the sleevedefines the inner surface of the housing and the insert defines thevalve seat; the sleeve has a hollow shape with an open upstream end anda partially closed downstream end, and the insert is secured at leastpartially within the upstream end of the sleeve; the partially closeddownstream end includes at least one opening therethrough that definesthe outlet of the housing; valve plug and the spring are retained withinthe sleeve and between the insert and the partially closed downstreamend of the sleeve; and a downstream portion of the valve body in nestedwithin the spring.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will now be described more fully with reference to theaccompanying drawings, in which:

FIG. 1 is a schematic view of a water system;

FIG. 2 is a cross-sectional side view of a flow control valve, in aclosed position;

FIG. 3 is a cross-sectional side view of the flow-control valve of FIG.2 , in an open position;

FIG. 4 is an axonometric cross-sectional view of the flow control valveof FIG. 2 , viewed from a downstream end of the valve;

FIG. 5 is an axonometric cross-sectional view of the flow control valveof FIG. 2 , viewed from an upstream end of the valve;

FIG. 6 is an exploded cross-sectional view of the flow control valve ofFIG. 2 ;

FIG. 7 is an exploded view of the flow control valve of FIG. 2 , shownin transparency;

FIG. 8 is an exploded view of another embodiment of a flow controlvalve, shown with part of the housing in transparency;

FIG. 9 is a cross-sectional side view of another embodiment of a flowcontrol valve, in a closed positon;

FIG. 10 is a downstream end view of the flow control valve of FIG. 9 ;

FIG. 11 is an exploded view of the flow control valve of FIG. 9 ;

FIG. 12 is a cross-sectional side view of a sleeve of a housing of theflow control valve of FIG. 9 ;

FIG. 13 is a downstream end view of the sleeve of FIG. 12 ;

FIG. 14 is a cross-sectional side view of an insert of the housing ofthe flow control valve of FIG. 9 ;

FIG. 15 is a downstream end view of the insert of FIG. 14 ;

FIGS. 16 and 17 are axonometric views of a bushing of the housing of theflow control valve of FIG. 9 , viewing an upstream end and a downstreamend of the bushing, respectively; and

FIGS. 18 and 19 are axonometric views of a valve plug of the flowcontrol valve of FIG. 9 , viewing an upstream end and a downstream endof the valve plug, respectively.

DETAILED DESCRIPTION OF EMBODIMENTS

The foregoing summary, as well as the following detailed description ofcertain embodiments will be better understood when read in conjunctionwith the accompanying drawings. As will be appreciated, like referencecharacters are used to refer to like elements throughout the descriptionand drawings. As used herein, an element or feature recited in thesingular and preceded by the word “a” or “an” should be understood asnot necessarily excluding a plural of the elements or features. Further,references to “one example” or “one embodiment” are not intended to beinterpreted as excluding the existence of additional examples orembodiments that also incorporate the recited elements or features ofthat one example or one embodiment. Moreover, unless explicitly statedto the contrary, examples or embodiments “comprising,” “having” or“including” an element or feature or a plurality of elements or featureshaving a particular property may further include additional elements orfeatures not having that particular property. Also, it will beappreciated that the terms “comprises,” “has” and “includes” mean“including but not limited to” and the terms “comprising,” “having” and“including” have equivalent meanings.

As used herein, the term “and/or” can include any and all combinationsof one or more of the associated listed elements or features.

It will be understood that when an element or feature is referred to asbeing “connected” another element or feature, that element or featurecan be directly connected to the other element or feature or interveningelements may also be present.

It will be understood that spatially relative terms may be used hereinfor ease of describing the relationship of an element or feature toanother element or feature as depicted in the figures. The spatiallyrelative terms can however, encompass different orientations in use oroperation in addition to the orientation depicted in the figures.

Reference herein to “example” means that one or more feature, structure,element, component, characteristic and/or operational step described inconnection with the example is included in at least one embodimentand/or implementation of the subject matter according to the subjectdisclosure. Thus, the phrases “an example,” “another example,” andsimilar language throughout the subject disclosure may, but do notnecessarily, refer to the same example. Further, the subject mattercharacterizing any one example may, but does not necessarily, includethe subject matter characterizing any other example.

Reference herein to “configured” denotes an actual state ofconfiguration that fundamentally ties the element or feature to thephysical characteristics of the element or feature preceding the phrase“configured to.”

Unless otherwise indicated, the terms “first,” “second,” etc. are usedherein merely as labels, and are not intended to impose ordinal,positional, or hierarchical requirements on the items to which theseterms refer. Moreover, reference to a “second” item does not require orpreclude the existence of a lower-numbered item (e.g., a “first” item)and/or a higher-numbered item (e.g., a “third” item).

As used herein, the terms “approximately” and “about” represent anamount close to the stated amount that still performs the desiredfunction or achieves the desired result. For example, the terms“approximately” and “about” may refer to an amount that is withinengineering tolerances that would be readily appreciated by a personskilled in the art.

FIG. 1 shows a water system generally identified by reference character10. The system includes a water supply 12, a distribution network 14, awater meter 16, a flow control valve 18 and a water consumer 20. Thewater supply 12 can be, for example, a reservoir maintained by a utilityor municipality. The reservoir may store a large volume of preferablypotable water for distribution to one or more water consumers 20. Thesevarious water consumers 20 may be, for example, dwellings such as housesor office buildings or other water outlets that are accessed byindividuals such as water fountains. The various water consumers 20 mayalso be industrial facilities, for example, bottling plants ormanufacturing facilities. The distribution network 14 can be, forexample, a number of water supply lines and/or return lines that areinterconnected to the water supply 12. This distribution network 14 caninterconnect the water consumers 20 to the water supply 12, with thewater consumers 20 being downstream of the water supply 12.

The water meter 16 is interconnected and in line with the distributionnetwork 14 upstream from an individual water consumer 20. The watermeter 16 may be of a conventional construction such as a positivedisplacement meter. Those of ordinary skill in the art will recognizeother types of water meters that can be used in the water system 10. Thewater meter 16 is typically maintained by the utility or municipalityand is operable to measure the volume of water used by an individualwater consumer 20 over a pre-determined period of time. As such, thewater meter 16 is instrumental in determining the water bill for thewater consumer 20. However, water meters typically measure volume alone,regardless of whether that volume includes liquid water (“water”) orwater with entrained water vapour and/or air (“water vapour”).Accordingly, measurements from water meters can be inaccurate and canoverestimate the volume of water actually consumed.

Increasing the pressure in the water meter can help to compress anyentrained water vapour and can help to reduce resultant inaccuracy andoverestimation of water usage. Accordingly, the flow control valve 18 ispositioned downstream of the water meter 16 and is intermediate thewater meter 16 and the water consumer 20. As will be described ingreater detail below, the valve 18 includes a spring biased valve headthat is triggered at a predetermined water pressure. Water is permittedto pass through the valve 18 and to the water consumer 20 only after abuild-up of sufficient water pressure upstream of the valve 18 isachieved. This can have the effect of compressing entrained water vapourupstream of the valve 18, which can increase the efficiency and accuracyof the water meter 16. In some valves, such as the one described in U.S.Patent Application Publication No. 2014/0182717, the valve head may beconnected to a shaft within the valve and may be free to move radiallywithin the valve when not engaging the valve seat. This radial movementof the valve head can cause the shaft to bend and eventually break.Accordingly, savings realized at the water meter 16 may be offset byrepair costs to the valve 18.

FIGS. 2 to 7 show an embodiment of the flow control valve 18. The valve18 is configured to remain closed and substantially prevent fluid flowtherethrough until a predetermined pressure is established upstream ofthe valve 18. The valve 18 comprises a housing 22, a valve seat 24, avalve head 26, a shaft 28, a spring 30, a guide assembly 32 and asupport 34.

The housing 22 is configured to support the various components of thevalve 18 and to secure the valve 18 to adjacent elements in the system10, such as the water meter 16 or piping to the water consumer 20. Thehousing 22 comprises an inlet 36 located at an upstream end of the valve18, an outlet 38 located at a downstream end of the valve 18 and flowpassage 40 that extends within the housing 22 between the inlet 36 andthe outlet 38. The housing 22 includes a flange for connecting to theadjacent elements in the system 10. Alternatively, the housing 22 mayinclude other suitable means for connecting, such as a pair of flanges(as shown in FIG. 8 ), threading or the like. The housing 22 comprises aplurality of interconnected pieces that are secured together byfasteners (as shown in at least FIGS. 6 and 7 ) or, alternatively, maybe secured by other known techniques such as welding, adhesives, etc. Inyet other embodiments, the housing 22 can be integrally formed as asingle piece.

The valve seat 24 has a complementary shape to the valve head 26 and isconfigured to form a seal with the valve head 26 when in a closedposition (as shown in FIG. 2 ). Specifically, when the valve head 26 isin firm contact with the valve seat 24. The valve seat 24 is defined bya narrowed portion 42 of the housing 22, within the flow passage 40. Thenarrowed portion 42 of the housing 22 is integrally formed in thehousing 22. Alternatively, the narrowed portion 24 can be formed by aninsert in the housing 22. A seal plane 44 is defined by the valve seat24 and the valve head 26 when in the closed position. As will beappreciated, fluid is substantially prevented from flowing past the sealplane 44 when the valve head 26 is in the closed position. Although theseal plane 44 is defined at the narrowest point in the valve seat 24 inthe present embodiment (as shown in FIGS. 2 and 3 ), the seal plane 44may be defined elsewhere on the valve seat 24 in other embodiments.

The valve head 26 has a complementary shape to the valve seat 24 and isconfigured to form a seal with the valve seat 24, when the valve head 26is in the closed position. The valve head 26 is moveable between theclosed position (shown in FIG. 2 ) and an open position (shown in FIG. 3), in a generally longitudinal direction of the valve 18. As will beappreciated, in the closed position the valve head 26 substantiallyseals and prevents fluid from passing through the valve 18. Whereas, inthe open position, the valve head 26 allows fluid to pass through thevalve 18, via the flow passage 40. Accordingly, the open position can bedefined as any position where the valve head 26 does not seal the valve18 and includes a fully open position, where the valve head 26 is spacedfrom the valve seat 24 by a maximum distance enabled by the valve 18. Tolimit obstruction from the valve head 26 when in the open position, thevalve head 26 may be completely withdrawn from the narrowed portion 42of the housing 22 when in the open position. In some embodiments, asshown, the valve head 26 has a flat upstream face 46 that does notextend upstream of the seal plane 44 in the closed position and which ispositioned downstream of the seal plane 44 in the open position.

The shaft 28 is configured to at least partially support and positionthe valve head 26 within the flow passage 40. Accordingly, the shaft 28is secured to a downstream face 48 of the valve head 26 and extendsrearwardly therefrom, and the shaft 28 is slidingly mounted within thehousing by support 34.

The spring 30 is configured to bias the valve head 26 to the closedposition and is further configured to maintain the valve head 26 in theclosed position until a predetermined pressure is applied to theupstream face 46 of the valve head 26 from fluid at the inlet 36.Accordingly, the spring 30 is secured within the housing 22, and has oneend abutting the downstream face 48 of the valve head 26 and an oppositeend abutting the support 34. In some embodiments, as shown, the spring30 may be positioned surrounding the shaft 28. When the predeterminedpressure is applied to the valve head 26 from fluid at the inlet 36, theforce of the spring 30 is overcome and the valve head 26 will move outof the closed position and away from the valve seat 24. This allowsfluid to flow through the open valve 18, via passage 40. As will beappreciated, the predetermined pressure at which the valve 18 opens willbe correlated to at least the strength of the spring 30 (i.e. thespring's stiffness constant), the amount the spring 30 is pre-compressed(i.e. the difference between the length of the spring 30 when relaxedand the length of the spring 30 when positioned between the support 34and the valve head 26 in the closed position) and the projected areas ofthe upstream face 46 and the downstream face 48 of the valve head 26.Accordingly, the predetermined pressure at which the valve 18 opens canbe tuned based on the desired application of the valve 18. Common valuesfor the predetermined pressure include 45 psi and 60 psi, but othervalues may also be used.

The guide assembly 32 is configured to constrain radial movement of thevalve head 26 (i.e. movement in a direction generally perpendicular tothe longitudinal axis 50 of the valve 18), particularly when movingbetween the open position and the closed position. Accordingly, theguide assembly 32 comprises a pair of guide rails that extend along asection of the flow passage 40. The guide rails 32 are secured withinthe housing 22 and extend along the entire section between the narrowedportion 42 and the support 34. One end of each of the guide rails 32 ispositively secured to the support 34 by fasteners or the like, and theopposite end of each of the guide rails 32 is pressed against thenarrowed portion 42 of the housing 22. The guide rails 32 arecircumferentially positioned on opposite sides of the valve head 26 toengage the valve head 26 and constrain radial movement thereof. Tofurther constrain radial movement, a pair of notches 54 are formed inthe valve head 26 (as shown in FIG. 7 ). Each of the notches 54 isshaped to slidingly receive a corresponding one of the guide rails 32 toincrease engagement between the valve head 26 and the guide rails 32.Accordingly, the notches 54 have complementary shapes to that of theguide rails 32 and are circumferentially spaced around the valve head 26at positions corresponding to that of the guide rails 32. For example,as shown in FIG. 7 , each of the notches 54 has a semi-circular shapethat corresponds to the circular cross-sectional shape of the guide rail32 and is circumferentially positioned on opposite sides of the valvehead 26, similar to the guide rails 32. However, other suitable shapesand positions will be apparent to those skilled in the art in view ofthe present description.

The support 34 is configured to slidingly mount the shaft 28 within thehousing 22. The support 34 is also configured to retain the spring 30and the guide assembly 32 within the housing 22. In some embodiments,the support 34 is secured to the housing 22 by fasteners. Alternatively,the support 34 may be integrally formed with the housing 22. In theembodiment shown in FIGS. 2 to 7 , the support 34 is secured to thehousing 22 by fasteners and comprises a reversible bar. The reversiblebar 34 has a first face 58 (shown in FIG. 5 ) and an opposite secondface 60 (shown in FIG. 4 ). The first face 58 is shaped to pre-compressthe spring 30 by a first amount and the second face 60 is shaped topre-compress the spring 30 by a second amount that is different than thefirst amount. That is, the first face 58 is shaped to pre-compress thespring 30 to a first length when the support 34 is secured to thehousing 22 and the spring 30 is positioned between the support 34 andthe valve head 26 in the closed position, with the spring 30 abuttingthe first face 58. While the second face 60 is shaped to pre-compressthe spring 30 to a second length when the support 34 is secured to thehousing 22 and the spring 30 is positioned between the support 34 andthe valve head 26 in the closed position, with the spring 30 abuttingthe second face 60. As shown in FIGS. 2 to 7 , the first face 58 is flatand the second face 60 includes an extension 62, which pre-compressesthe spring 30 farther than the flat first face 58. Accordingly, thesecond face 60 will pre-compress the spring 30 by a greater amount thanthe first face 58. This configuration allows the pre-compression of thespring 30 to be easily changed by reversing the orientation of thereversible bar 34 and, since the predetermined pressure is correlated tothe pre-compression of the spring, this configuration allows thepredetermined pressure at which the valve 18 opens to be easily changedas well. In the embodiment shown, the predetermined pressure may beapproximately 45 psi when the spring 30 is pre-compressed by the firstamount, using the first face 58, and may be approximately 60 psi whenthe spring 30 is pre-compressed by the second amount, using the secondface 60 with extension 62. Although, it will be appreciated that inother embodiments the support 34 may be shaped to pre-compress thespring 30 by other amounts to provide other predetermined pressures,depending on the desired application of the valve 18.

When the valve 18 is in use, the spring 30 maintains the valve head 26in the closed position until the predetermined pressure is applied tothe upstream face 46 of the valve head 26 from fluid at the inlet 36. Asdescribed above, increasing the pressure upstream of the valve 18 canhelp compress any entrained water vapour in the system 10 and can helpreduce resultant inaccuracy and overestimation of water usage. Once thepredetermined pressure upstream of the valve 18 is reached, the valvehead 26 will move out of the closed position and away from the valveseat 24, into the open position. Thus permitting water to flow throughthe valve 18, via the flow passage 40, to the water consumer 20.

When the predetermined pressure is applied to the valve head 26 fromfluid at the inlet 36 and the valve head 26 begins to move out of theclosed position, the guide rails 32 engage the sides of the valve head26 via the notches 54. This engagement helps to constrain radialmovement of the valve head 26 as it moves to the open position.Additionally, to constrain movement of the valve head 26 in radialdirections that would not otherwise abut the guide rails 32, the notches54 slidingly receive the guide rails 32 and increase engagement betweenthe valve head 26 and the guide rails 32. Thus, the guide assembly 32constrains radial movement of the valve head 26 when moving from theclosed position to the open position and helps to reduce the likelihoodthat the shaft 28 will bend or break.

FIG. 8 shows another embodiment of a flow control valve generallyidentified by reference character 118. As will be appreciated, the flowcontrol valve 118 is similar to the flow control valve 18, except thevalve head 26 includes a removable wear cap 64 and a body 66, and thehousing 22 includes a pair of flanges for connecting to the adjacentelements in the system 10.

The removable wear cap 64 is configured to form a seal with the valveseat 24, when the valve head 26 is in the closed position. Accordingly,the wear cap 64 has a complementary shape to that of the valve seat 24.As the flow control valve 118 is used over time, repeated sealing andunsealing of the wear cap 64 with the valve seat 24 can causedeterioration of the wear cap 64. Accordingly, the wear cap 64 isconfigured to be replaceable. That is, the wear cap 64 is secured to thebody 66 of the valve head 26 by fasteners or the like and can be removedand replaced with a new wear cap, as needed. Alternatively, the wear cap64 can be secured to the body 66 by threading, adhesives or othersuitable securing means. In the present embodiment, the wear cap 64 isformed of Teflon™. Although, in other embodiments, the wear cap 64 canbe formed of plastic, metal or other suitable materials. As shown in theembodiment in FIG. 8 , the notches 54 are formed in the wear cap 64 ofthe valve head 26. Though, in alternative embodiments, it will beappreciated that the notches 54 can be formed in the body 66 of thevalve head 26 and/or can be formed in both the body 66 and the wear cap64.

The body 66 of the valve head 26 is configured to support the wear cap64. Accordingly, the body 66 is secured to the wear cap 64, as describedabove, and the shaft 28 extends from the body 66 to the support 34.

Although the guide rails of the guide assembly 32 are shown anddescribed as extending along the entire section of the flow passage 40between the narrowed portion 42 of the housing 22 and the support 34, itwill be appreciated that in other embodiments the guide rails 32 mayextend along only part of that section. Bending of the shaft 28 isgenerally correlated to the length the shaft 28 is extended from thesupport 34, among other factors. Accordingly, in some embodiments it mayonly be necessary to constrain radial movement of the valve head 26 asthe shaft 28 becomes increasingly extended from the support 34, such aswhen the valve head 26 approaches the closed position. In suchembodiments, the guide rails 32, and hence the guide assembly 32, mayonly constrain radial movement of the valve head 26 during a portion ofthe movement between the closed position and the open position. In someembodiments, that portion of the movement may be when the valve head 26is adjacent the closed position. Thus, in some embodiments, the guiderails and/or the guide assembly 32 may extend along at least a part of asection of the flow passage 40, such as along at least half of thesection between the narrowed portion 42 and the support 34. In someembodiments, the guide rails and/or the guide assembly 32 may extendalong only the part of the section between the narrowed portion 42 andthe support 34 that is adjacent the valve seat 24.

Although the guide assembly 32 has been shown and described ascomprising a pair of guide rails 32 and a pair of notches 54, it will beappreciated that in other embodiments the guide assembly 32 may comprisethree or more guide rails 32 that are circumferentially positionedaround the valve head 26. In some embodiments, such as embodiments withthree or more guide rails 32, the notches 54 may be omitted entirely.Similarly, although the valve head 26 has been shown and described ascomprising a pair of notches 54, it will be appreciated that in otherembodiments the valve head 26 may comprise other types of voids, such asholes. In some embodiments, the valve head 26 may include a single voidin the form of a hole through the valve head 26 and the guide assembly32 may comprise a single guide rail 32 that passes through the hole toconstrain radial movement of the valve head 26.

Although the guide rails 32 have been shown and described as havingcircular cross-sectional shapes and the voids 54 have been shown anddescribed as having corresponding semi-circular shapes, in otherembodiments other suitable shapes will be appreciated. In someembodiments, the guide assembly 32 could comprise one or more guiderails 32 with T-shaped or I-shaped cross-sections that engagecorrespondingly shaped voids in the valve head to constrain radialmovement thereof. In other embodiments, the guide rails 32 may be wedgeshaped, with a wider face of the wedge shape being slidingly receivedwithin the void to constrain radial movement of the valve head 26. Avariety of suitable shapes for the guide rails 32 and the voids 54 willbe apparent to those skilled in the art, in view of the presentdescription.

FIGS. 9 to 19 show another embodiment of a flow control valve generallyidentified by reference character 220. The valve 220 can be used in thesystem 10, in a similar manner as the valve 18. The valve 220 isconfigured to remain closed and substantially prevent fluid flowtherethrough until a predetermined pressure is established upstream ofthe valve 220. The valve 220 comprises a housing 222, a valve plug 224and a spring 226. The valve plug 224 is secured within the housing 222and is movable between a closed position (shown in FIG. 9 ), wherein thevalve plug 224 substantially prevents fluid flow through the valve 220,and an open position, wherein the valve plug 224 permits fluid flowthrough the valve 220. The spring 226 is secured within the housing 222and biases the valve plug 224 towards the closed position.

The housing 222 is configured to movably retain the valve plug 224 andthe spring 226 therein. The housing 222 is further configured to besecured to adjacent elements of the system 10, such as the water meter16 and the piping to the water consumer 20. The housing 222 comprises asleeve 228, an insert 230 and a bushing 232. The sleeve 228, the insert230 and the bushing 232 are interconnected by press-fits, threading,adhesives or the like to form the housing 222. When assembled, thehousing 222 defines an inlet 234 at an upstream end of the valve 220, anoutlet 236 at a downstream end of the valve 220 and a flow passage 238through the valve 220 that extends from the inlet 234 to the outlet 236.The housing 222 further defines a valve seat 240 within the flow passage238 for sealingly engaging the valve plug 224, when the valve plug 224is in the closed positioned (as shown in FIG. 9 ). To secure the housing222 to the adjacent elements of the system 10, the housing 222 includesan outwardly extending flange 242 that can be secured between theadjacent elements of the system 10. For example, the flange 242 may bepinched between the water meter 16 and the piping to the water consumer20, such as between a downstream flange of the water meter 16 and anupstream flange of the piping to the consumer 20. In other embodiments,the flange 242 may be omitted and the housing 222 may be secured to theadjacent elements of the system 10 by threading, a pair of opposite endflanges, or other suitable securing mechanisms as would be appreciatedby a person skilled in the art.

The sleeve 228 is configured to retain the valve plug 224 and the spring226. The sleeve 228 has a hollow, generally cylindrical body 244 with anopen upstream end 246 and a partially closed downstream end 248. Aflange 250 extends outwardly from the upstream end 246 and is securelypositioned between the insert 230 and the bushing 232, when the housing222 is assembled. A plurality of openings 252 are formed in thedownstream end 248 to permit fluid flow therethrough and define theoutlet 236 of the housing 222. The upstream end 246 is configured tosecurely receive the insert 230 by a press-fit, threading, adhesive orthe like. The sleeve 228 is sized to slidably retain the valve plug 224and the spring 226 within the body 224 and between the insert 230 andthe partially closed downstream end 246, when the insert 230 is securedin the sleeve 228. When the housing 222 is assembled, the sleeve 228defines a portion of the flow passage 238 downstream of the insert 230.

The insert 230 is configured to secure the valve plug 224 and the spring226 within the sleeve 228. The insert 230 is further configured to formthe valve seat 240. The insert 230 has a generally ring-shaped body 254with a through-passage 256 that is narrower than an outer diameter ofthe valve plug 224. Accordingly, the valve plug 224 cannot pass throughthe through-passage 256. The body 254 includes a tapered inner surfacethat defines the valve seat 240. A flange 258 extends outwardly from thebody 254 at an upstream end thereof and is securely positioned adjacentthe flange 250 of the sleeve 228, when the housing 222 is assembled. Adownstream end of the insert 230 is sized to fit within the upstream end246 of the sleeve 228 and is configured to be secured to the sleeve 228by a press-fit, threading, an adhesive or the like. When the housing 222is assembled, the insert 230 defines the inlet 234 of the housing 222.The insert 230 further defines a portion of the flow passage 238downstream of the inlet 236.

The bushing 232 is configured to be secured to the adjacent elements ofthe system 10. The bushing 232 is further configured to be secured to atleast one of the sleeve 228 and the insert 230, to secure the housing222 to the adjacent elements of the system 10. The bushing 232 has agenerally ring-shaped body 260 that is sized to matingly receive thesleeve 228 therethrough and is configured to be secured to the sleeve228 by a press-fit, threading, an adhesive or the like. The bushing 232also includes the flange 242 of the housing 222, which extends outwardlyfrom the body 260 of the bushing 232 and is configured to be secured inthe system 10, as described above. The outer surface of the body 260 mayinclude a plurality of ridges 262.

The valve plug 224 is configured to substantially prevent fluid flowthrough the valve 220, when the valve plug 224 is in the closed position(shown in FIG. 9 ), and to permit fluid flow through the valve 220, whenthe valve plug 224 is in the open position. The valve plug 224 isfurther configured to constrain radial movement of the valve plug 224when moving between the closed position and the open position. The valveplug 224 comprises a valve head 264 and a valve body 266. The valve head264 is connected to the valve body 266 at an upstream end thereof. Thevalve head 264 has a complementary shape to the valve seat 240 and isconfigured to sealingly engage the valve seat 240 when the valve plug224 is in the closed position, to substantially prevent fluid flowthrough the valve 220 and to seal the flow passage 238. The valve head264 has a flat upstream face 268 that can be completely retracted fromthe valve seat 240 when the valve plug 224 is in the open position, tolimit obstruction of fluid flow through the valve 220. The valve body266 extends downstream from the valve head 264 and includes a pluralityof outwardly extending fins 270. The fins 270 extend radially beyond anouter diameter of the valve head 264 and are configured to slidinglyengage an inner surface of the sleeve 228 as the valve plug 224 movesbetween the closed position and the open position, to constrain radialmovement of the valve plug 224. The fins 270 are arranged in across-shape to constrain radial movement in substantially all radialdirections perpendicular to a longitudinal axis 274 of the valve 220(such as movement in both a vertical radial direction and a horizontalradial direction). Although, in other embodiments, the fins 270 may bearranged in another suitable shape, such as a Y-shape. Each of the fins270 includes a notch 272 at a downstream end thereof. The notches 272are sized to receive the spring 226 and are configured to permit adownstream portion of the valve body 266 to be nested within the spring226 (as shown in FIG. 9 ).

The spring 226 is configured to bias the valve plug 224 to the closedposition and is further configured to maintain the valve plug 224 in theclosed position until a predetermined pressure is applied to the valveplug 224 from fluid at the inlet 234. The spring 226 is positionedwithin the housing 222 and has one end abutting the valve plug 224 andan opposite end abutting the housing 222. As will be appreciated, thepredetermined pressure will be partially dependent on the force of thespring 226 biasing the valve plug 224 to the closed position. The forceof the spring is correlated to at least the strength of the spring 226(i.e. the spring's stiffness constant) and the amount the spring 226 ispre-compressed (i.e. the difference between the length of the spring 226when relaxed and the length of the spring 226 when positioned betweenthe valve plug 224 and the housing 222, with the valve plug 224 in theclosed position). Accordingly, the predetermined pressure can be tunedbased on the desired application of the valve 220. Common values for thepredetermined pressure include 45 psi and 60 psi, but other values mayalso be used.

When the valve 220 is in use, the spring 226 maintains the valve plug224 in the closed position until the predetermined pressure is appliedto the valve plug 224 from fluid at the inlet 234. When thepredetermined pressure is applied the valve plug 224, the force of thespring 226 will be overcome and the valve plug 224 will move out of theclosed position and towards the open position. As the valve plug 224moves out of the closed position, the valve head 264 will move away fromthe valve seat 240 and will no longer sealingly engage the valve seat240. This will allow fluid to flow through the valve 220, via the flowpassage 238, from the inlet 234 to the outlet 236. In this manner, thevalve 220 can substantially prevent fluid flow through the valve 220until the pressure upstream of the valve 220 is increased to thepredetermined pressure and, thereafter, permit fluid flow through thevalve 220. As described above, increasing the pressure upstream of theflow control valve in a system 10 can compress entrained water vapour inthe system 10 and may help reduce resultant inaccuracy andoverestimation of water usage by the water meter 16 in the system 10.

Moreover, as the valve plug 224 moves between the closed position andthe open position, the fins 270 of the valve body 266 will slidinglyengage the sleeve 228 of the housing 222 to constrain radial movement ofthe valve plug 224. Constraining radial movement of the valve plug 224may help to reduce wear and potential damage to the valve plug 224caused by vibration of the plug 224 within the housing 222.Additionally, constraining radial movement of the valve plug 224 as thevalve plug moves from the open position to the closed position may helpto align the valve head 264 with the valve seat 240 as the valve plug224 moves to the closed position, which may help to ensure sealingengagement between the valve plug 224 and the valve seat 240.

In an alternative embodiment, the fins 270 extend radially beyond theouter diameter of the valve head 264 and are configured to engage theinner surface of the sleeve 228 as the valve plug 224 moves between theclosed position and the open position, to constrain radial movement ofthe valve plug 224. Such a configuration may not constrain the radialmovement of the valve plug 224 as much as the previously describedembodiment, which slidably engages the inner surface of the sleeve 228.However, the radial movement of the valve plug 224 may be sufficientlyconstrained, depending on the implementation.

Although embodiments have been described above and are shown in theaccompanying drawings, it will be appreciated by those skilled in theart that variations and modifications may be made without departing fromthe scope defined by the appended claims, and the scope of the claimsshould be given the broadest interpretation consistent with thespecification as a whole.

That which is claimed: 1-20. (canceled)
 21. A flow control valve forfluid piping, the flow control valve comprising: a housing, the housingincluding a sleeve, an inlet, and an outlet; a valve plug, the valveplug having a valve head and a valve shaft secured thereto, the valveshaft having a first portion and a second portion, the first portionhaving a plurality of fins that extend radially outward and slidinglyengage an inner surface of the sleeve as the valve plug moves between anopen position and a closed position constraining radial movement of thevalve plug, wherein the second portion is radially smaller inlongitudinal cross-section than the first portion; and a coil springthat biases the valve plug towards the closed position, the coil springhaving a first end, a spring body and a second end, the first endabutting the first portion of the valve shaft, wherein the secondportion of the valve shaft is at least partially nested within thespring body.
 22. The flow control valve of claim 21, wherein the secondportion has a plurality of second fins radiating outwardly from thecentral longitudinal axis.
 23. The flow control valve of claim 21,wherein the sleeve has a circular cross-section.
 24. The flow controlvalve of claim 21, wherein the plurality of fins constrain radialmovement of the valve plug within the sleeve in a plurality of radialdirections.
 25. The flow control valve of claim 24, wherein the pluralof radial directions includes a first radial direction and a secondradial direction, and wherein the first radial direction is 90 degreesapart from the second radial direction.
 26. The flow control valve ofclaim 25, wherein the plurality of fins is arranged in a cross-shape.27. The flow control valve of claim 24, wherein the plurality of fins isarranged in a Y-shape.
 28. The flow control valve of claim 21, whereinthe coil spring biases the valve plug towards the closed position untila predetermined pressure is applied to the valve head of the valve plugfrom fluid at the inlet.
 29. The flow control valve of claim 21, whereinthe plurality of fins extend radially outward beyond an outer diameterof the valve head.
 30. The flow control valve of claim 21, wherein thevalve head has a flat upstream face that is configured to be completelyretracted from a valve seat when the valve plug is in the open position.31. The flow control valve of claim 30, wherein the housing comprises aninsert secured to the sleeve, and wherein the insert defines the valveseat.
 32. The flow control valve of claim 31, wherein the sleeve has ahollow shape with an open upstream end and a partially closed downstreamend, and wherein the insert is secured at least partially within theupstream end of the sleeve.
 33. The flow control valve of claim 32,wherein the partially closed downstream end includes at least oneopening therethrough that defines the outlet of the housing.
 34. Theflow control valve of claim 32, wherein the valve plug and the coilspring are retained within the sleeve and between the insert and thepartially closed downstream end of the sleeve, and wherein the secondend of the coil spring abuts the partially closed downstream end of thesleeve.